Closure.swift

self.errorView = {
    let view = UIView()
    view.backgroundColor = UIColor.redColor()
    view.addSubview({
        self.errorLabel = {
            let label = UILabel()
            label.textAlignment = .Center
            label.backgroundColor = UIColor.clearColor()
            return label
        }()
        return self.errorLabel
    }())
    return view
}()
self.view.addSubview(self.errorView)